A negative dynCTP reliably excludes focal myocardial fibrosis as defined by late gadolinium enhancement, with only 4.7% of non-ischemic segments showing LGE on CMR.
Does regadenoson-stress dynamic CT perfusion accurately detect ischemia and exclude myocardial fibrosis compared to 3-T stress CMR in symptomatic patients with suspected or known CAD?
Dynamic stress CT perfusion correlates acceptably with CMR for detecting ischemia, but its accuracy is compromised in segments with myocardial fibrosis, though a negative CT reliably excludes focal LGE.
Absolute Event Rate: 0% vs 0%
Abstract Introduction Dynamic stress CT perfusion (dynCTP) offers a 'one-stop' assessment of CAD's anatomy and function. However, myocardial fibrosis, common in atherosclerotic patients, often mimics inducible ischemia, leading to false-positive dynCTP results. Crucially, such patients, despite fibrosis's significant prognostic role in ischemic heart disease, are largely excluded from dynCTP validation studies. Objectives 1.- Evaluate the concordance between regadenoson-stress dynCTP and 3-T cardiac magnetic resonance (CMR) perfusion in symptomatic patients, including those with and without prior myocardial infarction. 2. Determine if a normal dynCTP result can reliably exclude focal myocardial fibrosis as defined by late gadolinium enhancement (LGE) CMR. Methods A prospective, single-center study enrolled symptomatic patients with suspected or known CAD who underwent regadenoson-stress dynamic dual-source CT and 3.0-T stress CMR. Myocardial blood flow (MBF) from CT was quantified using a 100 mL/100g/min cut-off for dichotomization. CT-derived MBF concordance with CMR findings (qualitative perfusion defects and LGE) was assessed. Mean time between CT and CMR examinations was 68 ± 30 days. Results Forty-two patients (age: 68 ± 11 years; 78% male) were included. Baseline characteristics: hypertension (76%), dyslipidemia (71%), smoking (48%), diabetes (31%), and prior CAD (31%). Mean radiation exposure for the CT protocol was 5.74 ± 3.2 mSv. Six hundred seventy-two myocardial segments were evaluated using both dynCTP and stress CMR. Overall ischemic/non-ischemic concordance was 78% (524/672). This rose to 81% (479/588) in non-LGE segments but fell to 58% (45/84) in LGE segments. Segment-level CT-MBF diagnostic performance for detecting perfusion defects yielded: in non-LGE CMR segments, sensitivity, specificity, PPV, and NPV were 65%, 87%, 60%, and 89%, respectively. For LGE segments, these values were 69%, 48%, 54%, and 64% Only 4.7% (26/558) of segments deemed non-ischemic by both techniques displayed LGE on CMR, a majority of which showed 50% transmurality Conclusion DynCTP and CMR perfusion correlated acceptably, particularly regarding specificity and NPV. However, in LGE segments, dynCTP accuracy was compromised, underscoring the importance of ascertaining LGE presence in patients undergoing dynCTP. A negative dynCTP reliably excludes focal LGE by CMR.
Medel et al. (Thu,) reported a other. A negative dynCTP reliably excludes focal myocardial fibrosis as defined by late gadolinium enhancement, with only 4.7% of non-ischemic segments showing LGE on CMR.